236 Geology of North Carolina, 



In passing westward from the tertiary formation of North 

 Carolina, we come to a belt of sandstone, of an average 

 width of twelve miles, which Prof. O. denominates the Inde- 

 pendent Coal Formation : and he is of opinion that it is a 

 continuation of the Richmond coal basin, and that both of 

 these belong to that deposit of sandstone, extending, accord- 

 ing to Maclure, from Connecticut river to the Rappahannock. 

 It crosses the state of North Carolina, but has not been ex- 

 amined farther south, though it undoubtedly extends into 

 South Carolina. A single bed only of coal ha.s been found 

 in North Carolina, not far from the Gulf on Deep river. It is 

 about a foot thick, is bituminous, and resembles the Rich- 

 mond and Liverpool coal. 



The sandstone of this formation furnishes valuable build- 

 ing stones. It is employed also for grindstones and whet- 

 stones. Underneath the coal formation, is found a bed of 

 millstone grit, which is employed for millstones, which bring 

 in market, from thirty to one hundred dollars a pair. 



Very little limestone has been found in connection with 

 this coal formation ; though the geological relations of this 

 rock in England would lead us to expect it immediately be- 

 neath the millstone grit. 



Succeeding to the red sandstone, or coal formation, on 

 the west, and forming a belt across the state wider than the 

 sandstone, we find what Prof. O. denominates the Great 

 Slate Formation, and Prof. Mitchell, the Ancient Transition 

 Rocks. The following synopsis of this formation from the 

 Report, will give the reader an idea of its geological and 

 mineralogical contents. 



1 . Argillite — black, blue, green, lilac, porcelanite ? Alu- 

 minous slate, light grey, yellow. 2. Chlorite-— common, 

 slaty. 3. Greenstone — unstratified, slaty, trap. 4. Por- 

 phyry — green, argillaceous, petro-siliceous. 5. Novacu- 

 lite — olive green, oil green, straw yellow, passing into chlo- 

 rite slate, passing into talc. 6. Petrosilex. 7. Hornstone — 

 yellow, dark green, zoned. 8. Siliceous Slate. 9. Talc — ■■ 

 fibrous, radiated, foliated, scaly, indurated. 10. Steatite — 

 common soapstone, light flesh red. 11. Sienite. 12. Quartz 

 — common, limpid, crystallized, milky, tabular, pseudomor- 

 phous, amethystine, granular. 13. Sulphate of Barytes — 

 lamellar, compact, granular. 14. Carbonate of Lime. 

 15. Epidote — massive, crystallized. 1-6. Tremolite. 17. Au- 

 gite — coccolite. 18. Hornblende- — olive green, slaty. 



